THE PRESENT INVENTION relates to a safety seat, and in particular, relates to a safety seat intended for use in a motor vehicle, such as a motor car.
It has been appreciated that if a motor vehicle, such as a motor car, is involved in a rear end collision, that is to say a following vehicle runs into the back of the car, the occupants of the struck car often suffer from neck injuries. Such injuries are commonly called "whiplash" injuries.
It is to be understood that during the rear-end collision of this type, the vehicle that is struck is subjected to a forward acceleration. This imparts a forward acceleration to the seats of the vehicle. The squab and back of each occupied seat engage the posterior and torso of the occupant of the seat and impart a substantial acceleration to the posterior and torso of the occupant. However, no corresponding acceleration is immediately imparted to the head of the occupant, as the head is not normally in contact with the seat, or with the head-rest that may be provided on the seat. The head is a part of the body that has substantial mass, and consequently the head has substantial inertia.
Preferably the movement of the head-rest has an upward component and a forward component relative to the back of the seat.
Conveniently the rearward movement occurs in two stages, the movement of the head-rest being associated with the first stage only of the two-stage movement.
Preferably the seat is provided with a recliner mechanism operable to selectively adjust the inclination of the back of the seat, the arrangement being such that the position of the head-rest relative to the back of the seat does not alter on actuation of the recliner mechanism.
Conveniently the head-rest is associated with a linkage, the linkage incorporating a component which remains fixed relative to the squab of the seat when the back of the seat effects the pivotal rearward movement when subjected to the substantial force.
Preferably the component is associated with the recliner mechanism and is adapted to move, together with the back of the seat, when the recliner mechanism is actuated.
According to another aspect of this invention there is provided a safety seat for use in a motor vehicle, the safety seat comprising a squab, a back associated with the squab and a head-rest associated with the back; the back being pivotally connected to support means for pivotal movement relative to the support means, between predetermined limits; the support means being pivotally connected to the squab to permit movement of
Thus, whilst the posterior and torso of the occupant of the vehicle are accelerated forwardly as a result of the rear-end collision, the head of the occupant of the vehicle initially remains stationary. This may cause the neck initially to adopt an "S"-shaped configuration as the lower part of the neck moves forwardly, whilst remaining vertical, and the upper part of the neck remains in its initial position. Subsequently, the head begins to rotate and the neck then occupies a curved configuration. The head subsequently moves forwardly. Research has shown that "whiplash" injuries may occur when the neck changes from the "S"-shaped configuration to the curved configuration, at a substantial speed.